The -- that played out of the popular American chain restaurant this weekend the manager missing later found dead a coworker looking for him collapsing. When rescuers got there they got sick to it was all carbon monoxide. Tonight this new sign on the door the building condemned unsafe to be inside and ABC's -- -- -- Has been at the scene all day on Long Island New York with the warning tonight for all of us. Responding to a 911 call of the woman fainting Saturday evening first responders immediately suspected -- carbon monoxide leak. Police and ambulance workers becoming ill themselves when they entered the Legal -- -- restaurant at this upscale shopping mall on Long Island. -- anybody out tax. -- -- -- evacuating that restaurant and two others officials made a grim discovery in the basement. Manager Stephen Nelson unconscious. The 55 year old father of two was later pronounced dead at the hospital wonderful -- is helping everybody. 27 others were hospitalized. All restaurant employees and first responders. Today fire officials say a faulty water heater flue pipe caused that deadly leak -- some defective heating equipment in the building creating a -- monoxide issue. Carbon monoxide is colorless odorless tasteless and very dangerous. Each year an average of 430. People -- from accidental carbon monoxide poisoning and more than 151000. Are hospitalized. Symptoms of carbon monoxide exposure include headache nausea and dizziness experts say the best treatment is fresh air immediately. And a defective alarm can be a lifesaver. You only have one carbon monoxide detector recommendations aren't pleased that detector closed students sleeping area. Investigators say the Legal Sea Foods was not required to have a carbon monoxide detector. -- for the victims all those made -- here have been treated at area hospitals and released.

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